Automatically Closing Dispenser Head

ABSTRACT

A dispenser head for a pressurized container has a channel for the medium to be dispensed that is connected to a dispensing opening and communicates with the container interior. A closure piston is arranged in the channel and closes off the dispensing opening. By applying pressure onto an actuating element, the valve of the pressurized container is actuated and the closure piston is moved into an opening position to release the dispensing opening. The closure piston has spaced-apart centering projections and flow passages therebetween for the medium. An end face of the closure piston remote from the dispensing opening has an elastic spring area with a head section interacting with the actuating element. The actuating element glides along the rounded head section when the closure piston moves into the opening and closing positions. The rounded head section is matched to the movement path of the actuating element.

BACKGROUND OF THE INVENTION

The invention relates to an automatically closing dispenser head for apressurized container with a dispensing valve for dispensing a medium,in particular viscous, foaming and/or gel-like products, wherein thedispenser head has a dispensing opening closable by a closure element,an opening mechanism by means of which, in the mounted state, thedispensing valve of the pressurized container can be opened, and achannel that opens into the dispensing opening for the medium. Thechannel comprises at least a first channel section and a second channelsection. By pressure being applied onto the actuating element, theopening mechanism is actuated and the closure element in the form of aclosure piston and the second channel section are moved relative to oneanother such that the closure element is moved out of the dispensingopening so as to release the dispensing opening.

Conventional pressurized containers with dispenser heads, for example,for foaming shaving creams and gels, usually have a dispensing openingthat cannot be closed so that, after use, it often happens that mediumwill continue to flow or to foam even though the actuating element is nolonger actuated; this leads to unpleasant residues in the area of thedispensing opening that dry up and contaminate newly dispensed freshmedium when using the pressurized container again. Moreover, as a resultof dried and clotted medium the dispensing opening often becomesclogged.

In order to avoid these disadvantages, the patent application EP 1 295812 A1 discloses an automatically closing dispenser head for apressurized container of the aforementioned kind in which the dispensingopening can be closed and opened by means of a closure element. Uponexerting pressure onto an actuating element, the opening mechanism isactuated and the closure element and the second channel section aremoved relative to one another. In this way, on the one hand, thedispensing valve is opened so that the pressurized medium can flow intothe channel. However, the medium can only exit through the dispensingopening once the closure element has released the second channelsection. By spring means, for example, a partially elasticallydeformable housing of the dispensing head, the respective elements canreturn into their original position relative to one another and to thepressurized container as the pressure being exerted onto the actuatingelement decreases so that the dispensing valve as well as the dispensingopening are closed again. In this way, leakage and post-foaming areeffectively counteracted.

However, it is a disadvantage that in the area of the dispensing openingthere are still residues of the dispensed medium. Moreover, reliablydosing the dispensing opening is a problem.

U.S. Pat. No. 5,205,443 discloses a dispensing head for the medium inwhich the closure element is designed to be elastic. An actuatingelement acts in a shaft-like area in front of the dispensing head of theclosure element on the closure element and, upon actuation, can causebending of this shaft causing the dispensing head to be moved into theinterior of the housing to thereby release a dispensing opening. Uponsubsequent release of the actuating element, the closure element isreturned into the dispensing opening causing still adhering residues ofthe medium to be forced into the dispensing opening so that thedispensing opening becomes clogged and post-foaming is unavoidable.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to configure anautomatically closing dispenser head for a pressurized container of theaforementioned kind in such a way that residues of the medium to bedispensed are effectively avoided and the dispensing opening can beclosed reliably.

In accordance with the present invention, this is achieved in that theautomatically closing dispensing head is characterized in that theclosure element is a movable closure piston that is provided withcentering projections that are arranged on the outer piston wall andspaced at a distance from one another and movable with the closurepiston, wherein between individual centering projections flow passagesfor the medium are provided and wherein on an end face of the closurepiston facing away from the dispensing opening an elastic spring area isprovided that is delimited at its end by a head section that interactswith the actuating element, wherein the head section has a roundedcross-sectional configuration and wherein the actuating element, duringopening and closing movement of the closure piston into the openingposition or closing position, glides along the rounded head section. Inthis connection, the rounded portion of the head section is matched tothe movement path of the actuating element.

In this way, an automatically closing dispenser head for a pressurizedcontainer is provided by means of which a medium can be dispensed in avery clean way. This is in particular the result of positionaldeviations of the closure piston relative to the housing parts beingreliably avoided by the presence of the centering projections that inthe second channel section are supported on the inner wall of the secondchannel section during the entire movement of the closure piston whenmoving into the opening position as well as when moving into the closingposition; this has the result that, in comparison to the aforementionedconfiguration of the prior part, no positional imprecisions during theclosing step occur in the area of the dispensing opening so that theclosure piston can be moved reproducibly and precisely into the openingand closing positions. This causes residues remaining in the dispensingopening to be reliably returned into the first channel section upontransfer of the closure piston from its opening position into theclosing position. Therefore, in the outer area of the dispensing openingof the dispenser head only minimal amounts of be dispensed medium willremain, if at all, that can be removed by the user with simple means,for example, simply by wiping with his finger or by rinsing off. Therisk of clogging of the dispensing opening is therefore reliablycounteracted.

Dispensing of the medium is not impaired because flow passages areprovided between the individual centering projections. The same holdstrue also for return of the medium once the pressure onto the actuationelement decreases and the closure piston moves into its closingposition. In order to provide a centering action that is uniform aboutthe circumference, the centering projections are preferably arranged inuniform distribution about a circumferential section of the closurepiston. It has been found in this connection that, for example, fourcentering projections that are uniformly distributed about thecircumference provide a precise movement and centering action of theclosure piston. In this connection it must be ensured that during theentire closure movement no tilting moments are possible across thelength of the closure piston so that the centering elements are locatednear the leading end of the closure piston. For this purpose, theleading end can also have a cross-sectional widened section that extendsabout the circumference of the closure piston so that it is providedwith an enlarged circumferential section on which the centering elementsare arranged. This also has the result that at this location an increaseof the flow rate of the medium to be dispensed is realized.

It is especially preferred that at the leading end, i.e., the end of theclosure piston that is facing the dispensing opening, a sealing elementis injection molded, preferably by means of an inner central supplyconduit within the closure piston and supply conduits that extendperpendicularly thereto and open into the outer surface of the closurepiston. Such a sealing material is comprised, for example, of a softplastic material, for example, TPE (thermoplastic elastomer) orsilicone. The closure piston can be made, for example, from ABS(acrylonitrile butadiene styrene), PP (polypropylene), or POM(polyoxymethylene) material, i.e., hard plastic materials.

In order to assist in the return of the material to be dispensed, thesecond channel section has a valve seat in which the closure piston withthe sealing element is to be completely seated in its closing position.For a slight slanted orientation of the closure piston relative to thehorizontal, a position is to be assumed by the closure piston wherein anupper area of the end of the closure piston at the dispensing side isarranged at a distance from the dispensing opening but otherwise doesnot project past the housing of the dispenser head in the area of thedispensing opening. Preferably, the closure piston is positioned withinthe valve seat such that its leading end is flush with the outer surfaceof the housing so that product residues can be easily removed. In thisway, material still adhering at this location can be returned by theseal and the valve seat into the lateral channel section.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is an embodiment of a dispenser head (schematically shown with aview of its interior) in the closed state of the closure piston.

FIG. 2 is an illustration analog to FIG. 1 with the closure piston inthe open position.

FIG. 3 is a detail view of a cross-sectional illustration of thedispenser head of the embodiment according to FIG. 1 in the area of thedispensing end and of the closure piston.

FIG. 4 is an illustration analog to FIG. 3 with the closure piston inthe opening position.

FIG. 5 is an illustration according to FIG. 3 illustrating the angledorientation of the closure piston relative to the horizontal.

FIG. 6 is a cross-sectional illustration in accordance with the sectionline VI-VI of FIG. 5.

FIG. 7 shows a detail view of the end of the closure piston that isfacing away from the dispensing opening and is provided with springelement and actuating element.

FIG. 8 is a detail view of the closure piston (in section) with innercentral conduit for injection molding the front end seal and the springelement.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The drawings identify parts that basically operate in the same way withidentical reference numerals. The dispenser head is generally identifiedby 1 and is preferably a unitary part of the pressurized container, notillustrated. The container has a housing 2 as well as a dispensingvalve, not illustrated in detail and only schematically shown as valve Vin FIGS. 1 and 2, for dispensing a medium, for example, viscous, foamingand/or gel-like products. This dispensing valve is assigned to theinterior of container in which the medium is contained and can beoperated by an opening mechanism.

The dispenser head has a dispensing opening that is comprised of a firstchannel section 4 and a second channel section 5 in communication withthe interior. The second channel section 5 has correlated therewith theclosure element formed as a closure piston 6 that controls thedispensing opening 3. The closure piston 6 is movable relative to thechannel section 5 so that it can be moved from its closing position(FIG. 1) into its opening position (FIG. 2).

In order to be able to carry out this movement, an actuating element 7is provided that is forced from its rest position (FIG. 1) into theactuating position and is thus pivoted. This actuating element 7actuates at the same time the opening mechanism (indicated schematicallyby the arrow M connecting valve V and the actuating element 7) withwhich the dispensing valve is opened.

As is disclosed in more detail in FIGS. 3, 4, 5, 6, and 8, at theleading end of the closure piston 6 a section 6.1 is provided that hascentering projections 6.2 that are supported on the inner wall of thesecond channel section 5 in the housing. In the illustrated embodiment,a total of four centering projections 6.2 are uniformly distributedabout the circumference and between them flow passage 6.3 for theproduct to be dispensed are provided. In the leading area of the secondchannel section 5, i.e., at its end that opens into the dispensingopening 3, the housing is provided with a valve seat 3.1.

This valve seat is correlated with the leading end of the closure piston6. This leading end of the closure piston 6 is provided with aninjection-molded seal 8 made of soft plastic material. The leadingpiston head 6.4 of the closure piston 6 has a configuration that iscongruent to the conical design of the valve seat so that it can beinserted completely into the valve seat, as illustrated in more detailin FIG. 3. The upper part shown in FIG. 3 is positioned at a distancerelative to the dispensing opening 3 (its front end). Nonetheless, inthe closed state the leading piston head 6.4 as a whole is arranged in arecessed position so that residues of the dispensed medium can be easilywiped off with a finger and, subsequently, the externally accessibleparts of the valve seat can be rinsed off. In this way it is reliablyprevented that residues that can dry up or clot remain in the area ofthe dispensing opening 3.

The return movement of the closure piston from its opening positionillustrated in FIG. 4 into the closing position of FIG. 3 causesresidues that are still remaining to be returned into the inner channelsection 5.

The end of the closure piston facing away from the dispensing opening 3has a spring element 9 of soft plastic material. The spring element 9 isprovided in the direction facing the actuating element 7 with a headsection 10 that has a rounded gliding surface 10.1. The spring element 9is at the same time also a sealing element so that product cannot exitfrom the container at this location. The actuating element 7 has acorrespondingly congruently shaped contact surface 7.1 that during thecourse of actuation, i.e., when suppressing the actuating element 7,glides along the gliding surface 10.1. As a result of the roundedconfiguration only relatively minimal friction forces are present; thisalso has the effect that no tilting moment can be transmitted onto theclosure piston (such disadvantageous tilting moments occur in prior artdevices).

Moreover, the desired almost horizontal position of the closure pistoncan be realized even though the actuating element is acted on in thevertical direction. Preferably, a longitudinal center axis of theclosure piston is oriented such that an angle a of less than 15 degreesto the horizontal is provided; see FIG. 5.

As a result of the minimal friction forces, the reduced tilting moment,and the provided centering projections 6.2, the closure piston can betransferred very precisely into the respective opening or closingposition. The inventive configuration provides optimized sealingbehavior and positioning in the closing position with simultaneousreturn of the medium.

In FIG. 8, the inner central conduit 6.5 is illustrated thatcommunicates with transverse conduits 6.6 for injection-molding the seal8 and the spring element 9.

The specification incorporates by reference the entire disclosure ofGerman priority document 10 2007 044 180.2 having a filing date of Sep.15, 2007.

While specific embodiments of the invention have been shown anddescribed in detail to illustrate the inventive principles, it will beunderstood that the invention may be embodied otherwise withoutdeparting from such principles.

1. An automatically closing dispenser head for a pressurized containerwith a dispensing valve for dispensing a medium, the dispenser headcomprising: a dispensing opening; an opening mechanism by means ofwhich, in the mounted state on the pressurized container, the dispensingvalve of the pressurized container can be opened; a channel for themedium to be dispensed, wherein the channel is connected to thedispensing opening and communicated with an interior of the pressurizedcontainer, wherein the channel has at least a first channel section anda second channel section; a closure piston arranged in the secondchannel section; an actuating element, wherein, by applying pressureonto the actuating element, the opening mechanism is actuated and theclosure piston and the second channel section are moved relative to oneanother such that the closure piston is movable from a closing position,in which the closure piston closes off the dispensing opening, out ofthe dispensing opening into an opening position, in which the closurepiston is moved out of the dispensing opening and releases thedispensing opening; wherein the closure piston has an outer piston wallprovided with centering projections; wherein the centering projectionsare positioned at a distance from one another and movable together withthe closure piston; wherein between the centering projections flowpassages for the medium are provided; wherein at an end face of theclosure piston facing away from the dispensing opening an elastic springarea is provided that is delimited remote from the dispensing opening bya head section interacting with the actuating element; wherein the headsection has a rounded cross-sectional configuration and the actuatingelement glides along the head section during movement of the closurepiston into the opening and closing positions; wherein the roundedcross-sectional configuration of the head section is matched to themovement path of the actuating element.
 2. The automatically closingdispenser head according to claim 1, wherein the centering projectionsare uniformly distributed about a circumference of the closure piston.3. The automatically closing dispenser head according to claim 1,wherein a longitudinal center axis of the closure piston is orientedsuch that an angle of less than 15 degrees to the horizontal isprovided.
 4. The automatically closing dispenser head according to claim1, wherein the closure piston has a piston head provided with aninjection-molded seal of a soft plastic material and wherein the secondchannel section has a valve seat into which, for assuming the closingposition of the closure piston, the seal of the closure piston isinserted completely or a partial spacing at least to a front end of thedispensing opening.
 5. The automatically closing dispenser headaccording to claim 4, wherein the closure piston has an inner centralconduit and, in the area of the seal, branching transverse conduitscommunicating with the inner central conduit and opening into the outerwall of the closure piston, wherein the central and transverse conduitsare used for injection-molding the seal.